US benchmark equity indexes ended lower on Tuesday after weaker-than-expected economic data and fresh tariff remarks from President Donald Trump.

* The Institute for Supply Management's Services Index slipped to 50.1 in July from 50.8 in June, missing expectations for an increase to 51.5. CNBC reported that the flat reading added to concerns about stagflation, rising inflation combined with weakening employment, following a soft July jobs report. Since services account for roughly 70% of the US economy, a slowdown in the sector could signal broader economic challenges ahead.

* President Donald Trump said he plans to introduce tariffs on semiconductors and pharmaceuticals within the next week, with drug import taxes potentially reaching 250%, The Wall Street Journal reported Tuesday. Swiss President Karin Keller-Sutter traveled to Washington without a formal invitation to discuss trade and attempt to avoid a 39% tariff, Bloomberg TV reported. Meanwhile, Trump's 25% duty on all Indian goods takes effect Thursday, and he warned tariffs could rise further within 24 hours, criticizing India for reselling Russian oil. India called the measures unjustified, noting that the US and EU also maintain trade with Russia.

* September West Texas Intermediate crude oil fell $1.10 to settle at $65.19 per barrel, while October Brent crude, the global benchmark, was last seen down $1.09 to $67.67.

* Axon Enterprise (AXON) shares were up more than 16% after the company posted better-than-expected Q2 results and raised its full-year revenue outlook late Monday.

* Gartner (IT) shares fell over 27% after the company posted Q2 adjusted earnings and revenue above forecasts but issued full-year guidance that missed analyst expectations.